Although rarely offered as an explicit argument against gay marriage, the idea that marriage is a sacred religious sacrament is one of the most important arguments for opponents and underlies much of the vehemence which motivates them in a way that the other arguments fail to explain. Indeed, if it werent for the idea that marriage is sacred, it seems unlikely that the debate would be as rancorous as it is.
To cite just one example, Senate Majority Leader Bill Frist stated in an interview on ABC: I very much feel that marriage is a sacrament and that should extend and can extend to that legal entity of a union between what has traditionally in our Western values been defined as between a man and woman. So I would support the amendment [banning gay marriage].
Marrage as Sacred
If marriage is sacred and if that sacral nature is derived from the idea that it has been blessed by God, then it will cease being sacred if Gods laws on marriage are not followed. The admittance of same-sex couples to the institution of marriage is not unlike letting an atheist deliver Holy Communion or allowing a Buddhist to become pope. Not following the rules that allow something to be a sacrament (sign of the sacred) is sacrilege (desecration or misuse of something sacred) and this is unacceptable to religious individuals and organizations.
There is nothing wrong with individuals or churches treating marriage as sacred or sacramental, but this is not a debate about what individuals or private institutions should be doing. It is a debate about how the government should treat people and how the laws on marriage should be written. Is there any obligation on the part of the government to define civil marriages in a manner that does not conflict with religious conceptions of the same?
With all due respect to religious people, the answer has to be no. It doesnt matter what their personal feelings are regarding marriage, nor does it matter how important a particular definition of marriage happens to be within their religious system. The government is separate from and independent of their religion and must define marriage in a manner consistent with the secular principles upon which the government and the laws are founded.
What if some religious groups declared that a certain type of tree were sacred would the government be obligated to prevent anyone from cutting down that species and making furniture out of it? Some religious groups prohibit the remarriage of people who have gone through civil divorce proceedings. Should the government therefore pass civil laws that prohibit divorce, or at least the remarriage of divorced persons?
Church & State
If the separation of church and state means anything, it must include the idea that people cannot be forced by the government to live according to the dictates of others religion. Just because one or many groups consider something sacred doesnt mean that everyone must be forced to do so as well. Just because one or many religious groups consider same-sex marriage a sacrilege doesnt mean that everyone else must be forced to define marriage in a way that would exclude gay couples.
It also isnt good enough for people to argue that same-sex marriage is against Gods will its fine if churches teach this, but no government is under any obligation to legislate in a manner that is consistent with what what any church interprets Gods will to be. That would be the very essence of what it means to live in a theocracy.
Marriage does not exist in order to further any mandates from anyones gods. Marriage does not exist simply in order to encourage and protect procreation. Marriage does not exist because it is a natural function. No, marriage exists because society finds that it is valuable and worthy to encourage and protect committed, intimate relationships that are pursued over an extended period of time. As an institution, marriage helps provide legal protection and stability to human relationships that might not otherwise survive problems and pressures under more informal terms. Financial and social benefits are thus conferred upon marital relationships because their long-term stability furthers general social stability.
So far, no government has suggested that any religious groups be forced to perform and recognize gay marriages - thats the flip-side of the separation of church and state and is as it should be. Just as the government is not obligated to define marriage along religious lines, religious groups are not obligated to define marriage along civil lines.
Marriage within a religion might be conceived as having been authored by God, but that is not and cannot be the starting basis for civil society. In civil society, marriage is authored by secular laws voted upon by representatives of the people and as interpreted by the courts. Thus, we are the authors of civil marriage - religion no longer plays any essential role.